Is electrostatics the cause of radio waves?

AI Thread Summary
Electrostatics alone does not produce radio waves; instead, electromagnetic waves are generated through electrodynamics. Maxwell's Equations govern the relationship between electric charges and their effects, showing that radio waves and light are electromagnetic waves with varying wavelengths and frequencies. Efficient radio signal transmission requires appropriate transmitters tailored to the desired frequency. The concept of "displacement current" introduced by Maxwell is crucial, as it describes how changing electric fields can create magnetic fields, leading to the propagation of electromagnetic waves. Ultimately, accelerating charges are essential for generating these waves, highlighting the limitations of relying solely on Coulomb's law.
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That is probably a badly worded question but I understand electrostatics and I want to send simple but efficient radio signals. If I switch on a strong charge in one place it'll effect a charge away from it depending on "Coulomb's law". How is this equation expanded to explain more efficient production of electromagnetic signals?
 
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Electrostatics is a simplified case of the more general "electromagnetism". The rules governing electric charges, electrical and magnetic effects, and any other related issues are given by Maxwell's Equations. These equations incorporate many other electrical/magnetic laws into a set of four equations that we can use to solve any problems regarding electromagnetism. In formulating these equations, Maxwell showed that radio waves, light, and other similar types of radiation are all electromagnetic waves with different wavelengths/frequencies.

The most efficient way of sending a radio signal is to simply use an appropriate transmitter for the wavelength/frequency you are sending.
 
To get EM waves, you need electrodynamics, not electrostatics. It's not a Coulomb's law effect. In fact, Coulomb's law breaks down if you have accelerating charges. One of the keys is Maxwell's "displacement current". This is sort of a ghost current that would go through a capacitor while it's charging up, in lieu of the actual current that's being held up there. It's sort of a symmetric law to Faraday's law which says that a changing magnetic field produces an electric field. Maxwell came along and said a changing electric field also produces a changing magnetic field. Changing magnetic field gives rise to changing electric and vice versa. So, you end up with a kind of chain reaction, which is an electromagnetic wave. It results when charges are accelerated.
 
Thread 'Motional EMF in Faraday disc, co-rotating magnet axial mean flux'
So here is the motional EMF formula. Now I understand the standard Faraday paradox that an axis symmetric field source (like a speaker motor ring magnet) has a magnetic field that is frame invariant under rotation around axis of symmetry. The field is static whether you rotate the magnet or not. So far so good. What puzzles me is this , there is a term average magnetic flux or "azimuthal mean" , this term describes the average magnetic field through the area swept by the rotating Faraday...
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